Abstract
An n-median semilattice (n≥3) is a meet-semilattice such that (i) every principal ideal is a distributive lattice and (ii) any n-element set of elements is bounded above whenever each of its (n-1)-element subsets has an upper bound. A 3-median semilattice is thus a median semilattice in the classical sense. In this note we demonstrate how the characteristic features of median semilattices carry over to the more general case of n-median semilattices.
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Communicated by I. G. Rosenberg
Research supported in part by ONR Grant N00014-90-1008.
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Bandelt, HJ., Janowitz, M.F. & Meletiou, G.C. n-median semilattices. Order 8, 185–195 (1991). https://doi.org/10.1007/BF00383403
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DOI: https://doi.org/10.1007/BF00383403